问题 单项选择题 A1/A2型题

有关激素水平测定正确的是()

A.不同时间测定正常值相同

B.激素水平高于正常一定提示功能异常

C.24小时尿中激素浓度的测定受影响更少

D.早餐前取血为了解基础激素水平的分泌

E.激素分泌与体位无明显相关

答案

参考答案:C

解析:激素分泌的特点是脉冲性、节律性及周期性,取血的瞬间只反映当时的水平,不一定反映总体分泌功能,而24小时的激素测定往往受瞬间分泌及节律性分泌的影响较少,结果更可靠。有些激素昼夜变化不大,节律性分泌不明显,可随时取血测定,如甲状腺激素;而昼夜变化明显者如ACTH及皮质醇、GH等则应根据其生理规律选择时间点取血,不同时间测定正常值也不同,需特别注意;如前所述,甲状腺炎时,激素水平可明显增高,但其并无功能亢进,可自发缓解;而低T3综合征时,T3水平虽低,但只是机体的一种适应性保护反应,并无功能低下。

判断题
单项选择题

American Museum of Natural History is one of the largest natural and historic museums in the world and one of the main natural history research and education centres in the United States, set up in 1869 and located in the west of the Central Park, Manhattan District, New York. It (1) 7 hectares in its total area, (2) classical types of buildings. The (3) of ancient creatures and humanity is (4) the first place of all the museums in the world, (5) the representative samples from South America, Africa, Europe, Asia and Australia were collected, besides those from the (6) country, the United States.

In the museum, there are five kinds of exhibits, including astronomy, mineralogy, human history, and animals in the (7) times and those in modern times. There are thirty-eight exhibition halls with different (8) from 500 to 1,500 square metres. Besides these, there is a Roosevelt Memorial Hall in (9) of President Roosevelt who supported the (10) of the museum, which is also used to have a special exhibition, showing the new important (11) on natural sciences and (12) affairs and social problems, and special topics connected closely with the life of the citizens. Besides this, it is also used for avocation (13) to have all kinds of scientific activities in the laboratories, centres of natural science and centres for citizens. There are more than 10 (14) research departments mainly (15) for collection of samples, research and work of publication.

In the museum, there are (16) and sub-libraries of Aulspond ancient amniote, with about 300 thousand books and magazines (17) natural history, many of (18) are very valuable monographs for the first edition. It has published many expert books and magazines, and a large number of propaganda materials, (19) which are the two magazines, Natural History and Members of Museum that have the biggest (20) of their magazines.

17()

A.of

B.for

C.from

D.on